This invention relates generally to pen caps and, more particularly, to a pen cap which in one position covers the point of the pen, and in a second position exposes the point of the pen for writing.
Pens have employed a variety of cap structures for providing protection for the pen point. The following U.S. patents illustrate developments in sliding caps for pencils, pens and the like.
U.S. Pat. No. 454,623 Baumgarten PA1 U.S. Pat. No. 856,148 Levingston PA1 U.S. Pat. No. 1,156,860 Heylmun PA1 U.S. Pat. No. 1,355,026 Austin PA1 U.S. Pat. No. 2,952,242 Rosso
Baumgarten (U.S. Pat. No. 454,623), for example, discloses a telescoping sleeve which protects the point of a pencil or pen. A slot is provided for sliding engagement with a retaining stud, and the sleeve is pushed into its retracted and covering positions. Levingston (U.S. Pat. No. 856,148) discloses a similar device in which a slidable cover sleeve engages an inner sleeve that is retained to the pencil by spring pressure. The cover sleeve is slid forward to protect the pencil point, or retracted to expose the point for writing.
Utilizing a pen to generate precise written characters requires that movement of the writer's hand be exactly communicated to the point of the pen. There must be no slop or lost motion between the pen point and the grip surface which the user grasps to hold the pen and direct the pen point.
Prior art cap structures, however, provide an imprecise, sloppy connection between the grip surface and the barrel of the pen when in the retracted position. Pens incorporating such cap structures cannot be readily utilized for precise writing.
Additionally, a pen should be comfortable to use. Prior art cap structures add considerable bulk to the grip area of the pen, and this bulk, combined with exposed projections and slot edges common to prior art pen caps, makes pens incorporating such cap structures uncomfortable to use.
It is accordingly an object of the invention to provide a cap structure which is captive on a pen, and which is moveable between two positions, namely a forward position which protects the point, and a rearward or retracted position which exposes the point for writing.
It is a further object of the invention to provide a cap structure which in its retracted position has a precise connection between the grip surface and the pen barrel, so that the pen can be utilized for precise writing.
It is yet another object of the invention to provide a cap structure which avoids excessive bulk, and which has a comfortable grip surface without exposed projections or slot edges.
It is still another object of the invention to provide a cap structure which is simple and inexpensive to manufacture, and which is readily adaptable to existing pen products such as common disposable pens.
Other general and specific objects of the invention will in part be obvious and will in part appear hereinafter.